Discrete Recovery Spectrum below 65°K in Irradiated Copper

An experiment on electron-irradiated copper is reported which demonstrates directly, indepeiident of analysis, that at least four regions of recovery exist in the temperature range 20 to 60 deg K. The sample was held at ~20 deg K during irradiation and was bombarded with 1.4-Mev electrons. The total radiation-induced resistivity increment was 2.99 x 10/sup -10/ ohm cm which corresponded to 2 x 10/sup -6/ atomic concentration of defects based on a value of 1.45 micro-ohm cm per atomic percent Frenkel pairs. The similar structurc observed in both the deuteron and electron experiments suggested that the discrete recovery stages are due to intrinsic processes and are not associated with chemical impurities. (A.C.)